Can’t use builder anymore after WP update to 4.6.1

Fatal error: Call to undefined function ctype_space() in /home/mysite.ru/docs/wp-content/plugins/so-widgets-bundle/base/inc/lessc.inc.php on line 2532

What’s wrong with it?

ctype_space($this->buffer[$this->count - 1]);

I’m deeply sorry, panicked. I’ve enabled ctype module in PHP hosting settings, now everything works fine.